为包含两个类的头文件构建C ++文件

Question

Object_t.h

class node_t;
typedef node_t * node_tptr;
class list_t;
typedef list_t * list_tptr;

typedef void * TYPE;   //void * means we can point to anything with a typecast

class node_t
{
   public:
      node_t(void);                      //default constructor
      node_t(TYPE newentity);   //constructor
      void set_next(node_tptr );
      node_tptr get_next(void);
      TYPE get_entity(void);
   private:
      node_tptr next;     //next link in the list
      TYPE entity;         //the entity
};

class list_t
{        
   public:
      list_t(void);                   //default constructor
      list_t(const list_tptr);    //copy constructor
      void insert(TYPE newentity);
      TYPE start(void);
      TYPE get_next(void);
   private:
      node_tptr head;
      node_tptr tail;
      node_tptr current;
};

The header file above contains the definitions for two different classes. I assume the next step would be to create a C++ file called object_t.cpp, but how would that work when there are two classes defined within the header file?

Answer 1

Unlike as in Java, a C++ file can contain more than one class implementation. Just implement both ;-)

Answer 2

It works because in the implementation file you define your functions using the scope resolution operator, eg

TYPE list_t::get_next(void) {}
nodet_ptr node_t::get_next(void) {}

which allows the compiler to correctly match up the declarations with the definitions.